Full-length cDNA that encodes feline α 1 -microglobulin (Feα 1 m)-bikunin was obtained from a feline liver and cloned using an oligo-capping method. The Feα 1 m-bikunin cDNA was found to contain 1284 nucleotides, and Feα 1 m was found to include an open reading frame encoding a polypeptide of 201 amino acids. The deduced amino acid sequence of Feα 1 m showed varying amino acid identity when compared with the published sequences of the related α 1 -m of other species, ranging from 71.1 to 82.1%. Feα 1 m mRNA expression was confirmed by reverse transcription polymerase chain reaction (RT-PCR) and real-time PCR analysis in the cerebrum, cerebellum, lung, heart, liver, spleen, pancreas, kidney, adrenal gland, and testicle. The highest Feα 1 m mRNA level was found in the liver.